Compositions and methods for improving proppant pack permeability and fracture conductivity in a subterranean well

Abstract

The present invention relates to enhancing fluid flow from subterranean formations. More particularly, this invention relates to providing improved proppant matrixes within fractures in a subterranean formation. An example of the methods of increasing the conductivity of a fracture in a subterranean formation comprises the steps of providing a fracturing treatment fluid comprising a proppant composition, the proppant composition comprising proppant particulates and a degradable material capable of undergoing an irreversible degradation downhole; introducing the proppant composition to the fracture; and allowing the proppant composition to form a proppant matrix having voids in the fracture.

What is claimed is: 
     
       1. A method of increasing the conductivity of a fracture in a subterranean formation comprising the steps of:
 providing a fracturing treatment fluid comprising a proppant composition, the proppant composition comprising proppant particulates and a degradable material that comprises one or more poly(orthoesters); 
 introducing the proppant composition to the fracture; and 
 allowing the proppant composition to form a proppant matrix having voids in the fracture. 
 
     
     
       2. The method of  claim 1  wherein the proppant particulates are selected from the group consisting of sand, walnut hulls, man-made proppant particulates and combinations thereof. 
     
     
       3. The method of  claim 1  wherein the proppant particulates have a size of about 10 to about 60 US mesh. 
     
     
       4. The method of  claim 1  wherein the proppant composition further comprises a curable resin, a tackifying agent, or both. 
     
     
       5. The method of  claim 4  wherein the curable resin is selected from the group consisting of epoxies, furans, phenolics, furfuryl aldehydes, furfuryl alcohols, and combinations thereof. 
     
     
       6. The method of  claim 1  wherein the proppant composition comprises interlocking proppant particulates. 
     
     
       7. The method of  claim 1  wherein the degradable material further comprises a degradable polymer or a dehydrated salt. 
     
     
       8. The method of  claim 7  wherein the degradable polymer comprises a second degradable material selected from the group consisting of polysaccharides, chitins, chitosans, proteins, aliphatic polyesters, poly(lactides), poly(glycolides), poly(ε-caprolactones), poly(hydroxybutyrates), polyanhydrides, aliphatic polycarbonates, poly(amino acids), poly(ethylene oxides), polyphosphazenes, and combinations thereof. 
     
     
       9. The method of  claim 1  wherein the degradable material further comprises a plasticizer. 
     
     
       10. The method of  claim 7  wherein the dehydrated salt comprises anhydrous sodium tetraborate or anhydrous boric acid. 
     
     
       11. The method of  claim 1  wherein the degradable material further comprises poly(lactic acid) and a compound chosen from the group consisting of sodium borate and boric oxide. 
     
     
       12. The method of  claim 1  wherein the degradable material further comprises a stereoisomer of a poly(lactide). 
     
     
       13. The method of  claim 1  wherein the proppant composition comprises a poly(lactic acid) degradable material and bauxite proppant particulates, the bauxite proppant particulates at least partially coated with a curable epoxy resin. 
     
     
       14. The method of  claim 1  wherein the degradable material is present in the proppant composition in an amount sufficient to create a desirable number of voids in the proppant matrix. 
     
     
       15. The method of  claim 1  wherein the degradable material is present in the proppant composition in an amount of about 0.1% to about 30% by weight of proppant particulates in the composition. 
     
     
       16. The method of  claim 1  wherein the degradable material further comprises particles having a rod-like shape. 
     
     
       17. The method of  claim 1  wherein the degradable material further comprises an inorganic or organic compound. 
     
     
       18. The method of  claim 17  wherein the inorganic or organic compound is selected from the group consisting of sodium acetate trihydrate, L-tartaric acid disodium, salt dihydrate, sodium citrate dihydrate, hydrate of an inorganic acid, hydrate of an inorganic acid salt, sodium tetraborate decahydrate, sodium hydrogenphosphate heptahydrate, sodium phosphate, dodecahydrate, amylose, starch-based hydrophilic polymer, cellulose-based hydrophilic polymers, and combinations thereof. 
     
     
       19. The method of  claim 1  wherein the degradable material is a composite. 
     
     
       20. A method of enhancing the permeability of a proppant matrix comprising the step of introducing a plurality of voids into the proppant matrix by a degradation of a degradable material that comprises one or more poly(orthoesters) within the proppant matrix. 
     
     
       21. The method of  claim 20  wherein the proppant matrix comprises a material selected from the group consisting of sand, walnut hulls, man-made proppant particulates, and combinations thereof. 
     
     
       22. The method of  claim 20  wherein the proppant matrix comprises a curable resin, a tackifying agent, or both. 
     
     
       23. The method of  claim 22  wherein the curable resin is selected from the group consisting of epoxies, furans, phenolics, furfuryl aldehydes, furfuryl alcohols, and combinations thereof. 
     
     
       24. The method of  claim 20  wherein the proppant matrix comprises interlocking proppant particulates. 
     
     
       25. The method of  claim 20  wherein the degradable material further comprises a degradable polymer or a dehydrated salt. 
     
     
       26. The method of  claim 25  wherein the degradable polymer is selected from the group consisting of polysaccharides, chitins, chitosans, proteins, aliphatic polyesters, poly(lactides), poly(glycolides), poly(ε-caprolactones), poly(hydroxybutyrates), polyanhydrides, aliphatic polycarbonates, poly(amino acids), poly(ethylene oxides), polyphosphazenes, and combinations thereof. 
     
     
       27. The method of  claim 20  wherein the degradable material further comprises a plasticizer. 
     
     
       28. The method of  claim 25  wherein the dehydrated salt is selected from the group consisting of anhydrous sodium tetraborate, anhydrous boric acid, and combinations thereof. 
     
     
       29. The method of  claim 20  wherein the degradable material further comprises poly(lactic acid) and a compound chosen from the group consisting of sodium borate and boric oxide. 
     
     
       30. The method of  claim 20  wherein the degradable material further comprises a stereoisomer of a poly(lactide). 
     
     
       31. The method of  claim 20  wherein the proppant matrix comprises a poly(lactic acid) degradable material and bauxite proppant particulates, the bauxite proppant particulates being at least partially coated with a curable epoxy resin. 
     
     
       32. The method of  claim 20  wherein the degradable material is present in the proppant matrix in an amount sufficient to create a desirable number of voids in the proppant matrix. 
     
     
       33. The method of  claim 20  wherein the degradable material is present in the proppant matrix in an amount of about 0.1% to about 30% by weight of the proppant matrix. 
     
     
       34. The method of  claim 20  wherein the degradable material comprises particles having a rod-like shape. 
     
     
       35. The method of  claim 20  wherein at least a portion of the voids in the proppant matrix are channel-like in shape. 
     
     
       36. The method of  claim 20  wherein the proppant matrix has a conductivity equal to or greater than 4500 darcies at a pressure of about 2000 psi. 
     
     
       37. The method of  claim 20  wherein the proppant matrix has a conductivity equal to or greater than 4500 darcies at a pressure of about 4000 psi. 
     
     
       38. The method of  claim 20  wherein the proppant matrix has a conductivity equal to or greater than 4000 darcies at a pressure of about 6000 psi. 
     
     
       39. A method of increasing the conductivity of a fracture in a subterranean formation comprising the steps of:
 providing a fracturing treatment fluid comprising a proppant composition, the proppant composition comprising proppant particulates and a degradable composite material that comprises one or more poly(orthoesters); 
 introducing the proppant composition to the fracture; and 
 allowing the proppant composition to form in the fracture a proppant matrix having voids. 
 
     
     
       40. The method of  claim 39  wherein the proppant particulates are selected from the group consisting of sand, walnut hulls, man-made proppant particulates, and combinations thereof. 
     
     
       41. The method of  claim 39  wherein the proppant particulates have a size of about 10 to about 60 US mesh. 
     
     
       42. The method of  claim 39  wherein the proppant composition further comprises a curable resin, a tackifying agent, or both. 
     
     
       43. The method of  claim 42  wherein the curable resin is selected from the group consisting of epoxies, furans, phenolics, furfuryl aldehydes, furfuryl alcohols, and combinations thereof. 
     
     
       44. The method of  claim 39  wherein the proppant composition comprises interlocking proppant particulates. 
     
     
       45. The method of  claim 39  wherein the degradable composite material further comprises a degradable polymer or a dehydrated salt. 
     
     
       46. The method of  claim 45  wherein the degradable polymer is selected from the group consisting of polysaccharides, chitins, chitosans, proteins, aliphatic polyesters, poly(lactides), poly(glycolides), poly(ε-caprolactones), poly(hydroxybutyrates), polyanhydrides, aliphatic polycarbonates, poly(amino acids), poly(ethylene oxides), polyphosphazenes, and combinations thereof. 
     
     
       47. The method of  claim 45  wherein the dehydrated salt is selected from the group consisting of anhydrous sodium tetraborate or anhydrous boric acid, and combinations thereof. 
     
     
       48. The method of  claim 39  wherein the degradable composite material further comprises poly(lactic acid) and a compound chosen from the group consisting of sodium borate and boric oxide. 
     
     
       49. The method of  claim 39  wherein the degradable composite material further comprises a stereoisomer of a poly(lactide). 
     
     
       50. The method of  claim 39  wherein the proppant composition comprises a poly(lactic acid) degradable material and bauxite proppant particulates, the bauxite proppant particulates being at least partially coated with a curable epoxy resin. 
     
     
       51. The method of  claim 39  wherein the degradable composite material is present in the proppant composition in an amount sufficient to create a desirable number of voids in the proppant matrix. 
     
     
       52. The method of  claim 39  wherein the degradable composite material is present in the proppant composition in an amount of about 0.1% to about 30% by weight of proppant particulates in the composition. 
     
     
       53. The method of  claim 39  wherein the degradable composite material further comprises particles having a rod-like shape. 
     
     
       54. The method of  claim 39  wherein the degradable composite material further comprises an inorganic or organic compound. 
     
     
       55. The method of  claim 54  wherein the inorganic or organic compound is selected from the group consisting of sodium acetate trihydrate, L-tartaric acid disodium, salt dihydrate, sodium citrate dihydrate, hydrate of an inorganic acid, hydrate of an inorganic acid salt, sodium tetraborate decahydrate, sodium hydrogenphosphate heptahydrate, sodium phosphate, dodecahydrate, amylose, starch-based hydrophilic polymers, cellulose-based hydrophilic polymers, and combinations thereof. 
     
     
       56. A method of enhancing the permeability of a proppant matrix comprising the step of introducing a plurality of voids into the proppant matrix by a degradation of a degradable composite material within the proppant matrix. 
     
     
       57. The method of  claim 56  wherein the proppant matrix comprises a material selected from the group consisting of sand, walnut hulls, man-made proppant particulates, and combinations thereof. 
     
     
       58. The method of  claim 56  wherein the proppant matrix comprises a curable resin, a tackifying agent, or both. 
     
     
       59. The method of  claim 58  wherein the curable resin is selected from the group consisting of epoxies, furans, phenolics, furfuryl aldehydes, furfuryl alcohols, and combinations thereof. 
     
     
       60. The method of  claim 56  wherein the proppant matrix comprises interlocking proppant particulates. 
     
     
       61. The method of  claim 56  wherein the degradable composite material further comprises a degradable polymer or a dehydrated salt. 
     
     
       62. The method of  claim 61  wherein the degradable polymer is selected from the group consisting of polysaccharides, chitins, chitosans, proteins, aliphatic polyesters, poly(lactides), poly(glycolides), poly(ε-caprolactones), poly(hydroxybutyrates), polyanhydrides, aliphatic polycarbonates, poly(amino acids), poly(ethylene oxides), polyphosphazenes, and combinations thereof. 
     
     
       63. The method of  claim 62  wherein the dehydrated salt is selected from the group consisting of anhydrous sodium tetraborate, anhydrous boric acid, and combinations thereof. 
     
     
       64. The method of  claim 56  wherein the degradable composite material further comprises poly(lactic acid) and a compound chosen from the group consisting of sodium borate and boric oxide. 
     
     
       65. The method of  claim 56  wherein the degradable composite material further comprises a stereoisomer of a poly(lactide). 
     
     
       66. The method of  claim 56  wherein the proppant matrix comprises a poly(lactic acid) degradable material and bauxite proppant particulates, the bauxite proppant particulates being at least partially coated with a curable epoxy resin. 
     
     
       67. The method of  claim 56  wherein the degradable material is present in the proppant matrix in an amount sufficient to create a desirable number of voids in the proppant matrix. 
     
     
       68. The method of  claim 56  wherein the degradable composite material is present in the proppant matrix in an amount of about 0.1% to about 30% by weight of the proppant matrix. 
     
     
       69. The method of  claim 56  wherein the degradable composite material comprises particles having a rod-like shape. 
     
     
       70. The method of  claim 56  wherein at least a portion of the voids in the proppant matrix are channel-like in shape. 
     
     
       71. The method of  claim 56  wherein the proppant matrix has a conductivity equal to or greater than 4500 darcies at a pressure of about 2000 psi. 
     
     
       72. The method of  claim 56  wherein the proppant matrix has a conductivity equal to or greater than 4500 darcies at a pressure of about 4000 psi. 
     
     
       73. The method of  claim 56  wherein the proppant matrix has a conductivity equal to or greater than 4000 darcies at a pressure of about 6000 psi.